Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf

These are seal dive data used in the paper "Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf"

The seal dive depths provide new ocean depth information from over 500,000 individual dives from 265 seals on the East Antarctica continental shelf. The seal tags have a post-processed position uncertainty of 2-3 km, and provide transmitted depth data with a resolution of 10-25 m. About 25% of these seal dives were, on average, 220 m (sometimes over 1000 m) deeper than the interpolated seafloor in the International Bathymetric Chart of the Southern Ocean Version 2

Each row is an individual dive collected by a SMRU CTD-SLDR and transmitted via system Argos. Max_depth is the maximum depth reached by the seal on that dive.

The lons and lats are estimates of the seals location at the end of that dive and were calculated using the AniMotum package in R, which uses a state Space Model to estimate a location for each dive. The uncertainty of these locations has been quantified to be a median error of 3.2 km (95th percentile = 12.1 km), relative to near-simultaneous GPS locations for the same seals (Jonsen, I. D. et al. A continuous-time state-space model for rapid quality control of Argos locations from animal-borne tags. Move. Ecol. 8, 31 (2020). https://doi.org:10.1186/s40462-020-00217-7).

The columns are:

Id = seal identifier
date = date/time in YYYY-mm-dd HH:MM:SS format
lon = longitude
lat = latitude
max_depth = maximum depth of the dive. Depths are negative to match the IBCSO data
ibcso2 = IBCSO V2 bathymetry at that point
dfb = distance from bathymetry calculated as ibcso2-depth, so that a positive value indicates the dive was deeper than IBCSO
species= species of seal that collected the data (Mirounga leonina or Leptonchtyes weddellii)

本数据集为论文《南大洋鳍足类动物为南极东大陆架提供水深测绘视角》（原论文英文标题：Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf）中使用的海豹潜水数据集。

该数据集涵盖南极东大陆架海域265头海豹的50余万次独立潜水记录，其所获取的潜水深度数据可为海洋水深信息提供全新的观测补充。海豹搭载的标记设备经后处理后的位置不确定性为2-3千米，传输的深度数据分辨率达10-25米。其中约25%的潜水记录的平均深度较南大洋国际水深图第二版（International Bathymetric Chart of the Southern Ocean Version 2，IBCSO V2）的插值海底地形深220米，极端案例下潜水深度甚至超过1000米。

每条记录对应一次由SMRU CTD-SLDR设备采集、经Argos系统传输的独立潜水。其中max_depth字段代表该次潜水中海豹达到的最大深度。

潜水结束时的海豹位置通过R语言的AniMotum包计算得到，该工具利用状态空间模型（state Space Model）为每次潜水估算位置。结合同批海豹的近同步GPS定位数据验证，此类位置估算的中位误差为3.2千米（95%分位数为12.1千米），相关研究参见：Jonsen, I. D. 等. 用于快速质控动物标记设备Argos定位的连续时间状态空间模型. Move. Ecol. 8, 31 (2020). https://doi.org:10.1186/s40462-020-00217-7。

各字段说明如下：
Id：海豹唯一标识符
date：日期与时间，格式为YYYY-mm-dd HH:MM:SS
lon：经度
lat：纬度
max_depth：潜水最大深度，为与IBCSO数据格式保持一致，深度值以负数表示
ibcso2：对应点位的IBCSO V2水深数据
dfb：水深间距，计算公式为ibcso2 - depth，正值代表该次潜水深度超过IBCSO记录的海底水深
species：采集数据的海豹物种，为南象海豹（Mirounga leonina）或韦德尔氏海豹（Leptonchtyes weddellii）